This invention relates to a multi-layered solid combustible carbonized wood article having fast ignition without emission of carbon monoxide, and, more particularly, to fire logs, barbecue briquettes, wood fire starters, and similar articles which ignite without adding wax (in the case of artificial wax-based fire logs) or a separate starter fluid (in the case of barbecue charcoal).
It is known to make fire logs, barbecue charcoals, wood fire starters, and the like with igniting properties. Such articles may be lighted with a match rather than requiring the use of kindling (in the case of an artificial fire log with wax) or a starter fluid (in the case of barbecue charcoal). The objectives in the use of these articles differ somewhat, the objective in the case of the fire log being to produce heat and a pleasing visual appearance over a long period of time, and the objective in the case of the barbecue charcoal being to provide an intense heat for cooking, over a shorter period of time.
Some commercial wax-based artificial fire log products, for example, are formed of a molded mixture of sawdust and wax in approximately equal proportions. The wax is ignited with a match, and the burning wax in turn provides a flame to initiate and promote the burning of the sawdust. The available commercial products require 10-12 minutes to reach full flame. After the burning has reached full flame, the height of the flame decreases over the burning life of the fire log, a disadvantage because the visual appearance of the burning process is important to the consumer. There is an unpleasant odor from the burning wax, as well as heavy smoke produced when a substantial amount of the wax has been burned, which is environmentally unsound.
Various techniques have been utilized to overcome these shortcomings. Multilayer structures have been used. Such multilayer structures have a top fire-igniting layer with constituents to achieve rapid initial combustion, a fire-catching layer with constituents to sustain the initial combustion so as to catch the article on fire, and a bottom layer with the fire-sustaining fuel to generate heat over a long period of time. Depending upon the compositions of the layers, the time for the flame to propagate from the fire-igniting layer to the fire-catching layer and thence to the article may be relatively long, resulting in excessive smoke, toxic gases, and odor. There may also be the risk of uncontrolled burning, and even explosion, depending upon the constituents of the layers.
There is, accordingly, a need for an improved approach to fast, easily igniting, rapid-full-flame, clean, environmentally friendly, combustible articles such as non-wax-based artificial fire logs and barbecue briquettes that do not require the use of starter fluid. The present invention fulfills this need, and further provides related advantages.